This patch series cleans up the --enable-<feature> handling part of configure.ac. It changes the testing of features so that they are all done in the same way. The linecount of configure.ac is reduced from around 1800 with 450 lines. This is partly because os using macro's, partly due to simplification of if/else logic and also a bit due to rewriting stuff to one line. I think the readability of configure.ac is greatly improved. The only feature that is lost is the error message when --enable-foo=arg is used with arg something other than yes or no. Instead now silently the default is used. This is no big loss IMHO, because usually just --enable-foo or --disable-foo is given to configure. Maarten [PATCH 1/7] build-system: Simplify AC_ARG_ENABLE usage [PATCH 2/7] build-system: Use AS_IF macro for configure output [PATCH 3/7] build-system: Move AC_DEFINE to separate line with AS_IF [PATCH 4/7] build-system: Move dependency error messages to outer scope [PATCH 5/7] build-system: Replace some more conditionals with AS_IF [PATCH 6/7] build-system: Rearrange database selection [PATCH 7/7] build-system: Small fixes
